Fixation vs. finalization
Fixation is the process of writing the lead-in and lead-out information to the disc. This process finishes a writing session and creates a table of contents. Fixation is required for a CD-ROM or CD-Audio player to play the disc. Discs which are "fixated for append" can have additional sessions recorded, with their own session lead-in and lead-out, creating a multisession disc. When a disc is "finalized" the absolute lead-in and lead-out for the entire disc is written, along with information which tells the reader not to look for subsequent sessions. This final table of contents (TOC) conforms to the ISO 9660 standard.